SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1b21b48addc1fc3a935f540e42ea721bb2a1fcfd2816e17a967c07c76a7d9fbc' 
  AND token = 'M3QFDK7hd1boSOEQUxaI3bhkmcBEodyguSY3SkjNxsY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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