SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd6164933f883da0742a16d65f2f91f28e858c17ad4158be45a7802bc45a03fb8' 
  AND token = 'nezlxGxK+XCK3iOhHimCl6bqsoYlYACgu8eIgVJsozQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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