SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57455cdab1907ccd59caa81a89689b60ab36d4faae9b0bb9be7a38b5f745363a' 
  AND token = 'UcyL9rA4TPRxocTBwyaURQmRlWxZ3GGe6GBGLOLLIZY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}