SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba84aeb425137eca66353eb69ccc779430e142580a249e76e1b510527dfa1e92' 
  AND token = 'dlcdnOJQ4Hr95dyCEpNrR1aAAat4wCWPA/1VssmT8vU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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