SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a12f32294575d2f06245439b0e1f4869693b41889b439ce1bdac66c120c745fb' 
  AND token = 'DdraSYyVfSk5lnqTbhumzVd/BDQ3Mw8XZ/YnLGeuews=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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