SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd75c5fbab5444335e26bdb4bb5f749b9ae80619df5e4a8e37f44e99e2e59568b' 
  AND token = 'aPJtXIOlCpot99MmJSGyvtMUaAIVM19+KUTUNMFDF/4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}