SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '718bb3ddb7f2d423fcaa9ef73adee1248046c613071ec3855c617d81324ba2b2' 
  AND token = 'w0OU4RJ3wFFo7HvO6lCGvV/0qmSOhAhecXJlB0FCXEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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