SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '34c60745bf86ed24a90661f2ddb368d6c477d75a9a543eeff66472fa3c12a392' 
  AND token = 'fNtqq56DCtIW/QkLw0EfFsF2qxGiAi+UknC5/FPpv2g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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