SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '19609cd1a31f038b436588d41307b42827ac3f571bb5f9d34fdfec80760938c1' 
  AND token = '2joeurGH72CR0vUUM8iUUoFa7EmL+aiOAFQaY+GTYq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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