SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7314df53a1d2fd1f255c76c87e1382bbfc606f68f6aba325f828bebe4fb7cdc' 
  AND token = 'QQld9s4fNXp7z00DQhs7QJ+lG0cUzlDS8obUP9eVSfA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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