SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '977e9f2d1dd447c326c0628e5cd68887a532da1f732fc08bb2dcde3d65d14190' 
  AND token = 'ZuDGbQhGgE8g4rs6Avo3PuJp+b8l36JFdkv9fkcfFzA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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