SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '892f5fb72e478615e41f56983a6d973f71c5bd6e0c60f31b5e3a4f8c6655cf29' 
  AND token = 'jTZYiuQ2qzvVjMPNHmxwmmPKU1elTjRBOiL+37vZthY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}