SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2442b74010ca7efc9e2ab346f470dd6ccdfa61bf905730f93e1c4d1aed01d5ee' 
  AND token = 'cTzxrQWVwzeTvdEKquFKRgywpYXhUv1j/DM926CncdQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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