SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c2e0334d63e6ef5b33972fdbf3b6d8666c7e84883ca081c221da0b538884ebbc' 
  AND token = '6cHRJ+ZNbKk5iHYr32Rd7NgPQFAxvg9RK6kJfmIkGiA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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