SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2d09456b1ad0af802ae3aa6b6a35afac6caae17771d210ed5e788ff68dca346' 
  AND token = 'rZLqQlxkiMDNA0aW6gKIhvGSPnuJ812rDRPSDftJEL4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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