SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '37d393c1a64811d2848f1fe536b5bb003acb4ef38fefa861f8d16344ca05fcd1' 
  AND token = 'Sfl7NYQJ6rtL29Kor00vCpWgacZVtPlEhuEoUXbhCHQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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