SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25a2bc72213f28e0eb82e2a4098a92d6cd43bccbe0342fa171b46ab75ab0525f' 
  AND token = 'nuZfIePdvHpODLReCOh9W9FNx+IRPxuiQbDuxhBLC8A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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