SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aedee42ff3841b08150cdd53ae8c8c1ef871105481798645db2c4dffef183a57' 
  AND token = 'iiuPueysvS2FbeRTljoy/yU11YZp+M7UihPpMDNcW1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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