SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7527adba6011bf5f6d39b16a23f8332675f3095d914e3f420ff6953cb684b04b' 
  AND token = 'muKXJ2x9Hjb4i6sfIBAWAslDYtIE0gIk7bL+UmzNZnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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