SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '948be0a58241cb4e2ba1e5ffc19d65afbf1144a13442674cd958495ee45d63e0' 
  AND token = 'xGW6EFDhPHqGUJl9reCQyFZHIF6BG/jGziNeXNO+nyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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