SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f0a664bd825aeb31c9fd43879f32f500b61157104ebd2164eb7e8795ad23f988' 
  AND token = '0Ypym9q0XtS0ABVy60FgMN7gubG+zRdU9+akPh653Is=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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