SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd096810141f2d739108f2292108032fa50965607dd6795cd0feddb1694d53e60' 
  AND token = 'MEnexLd8RWFVo1wmJccPF7IvNreRpkImRMHXpZT1/58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00071

JSON explain

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