SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fcb97a3684c24a2454d463c38ab9f8037c19d8e9949b1beb181fbf5d08fdc3a' 
  AND token = 'SDeV1K4VzPYX5/H2c8lL6u+6RIg2q2uTI1AF9TUvSqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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