SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d2d5294361497471f25736549b844461dec8ebd94b939b2a3bcb87c0b667b1b' 
  AND token = 'gvufPRJNioNBBuIi0yr7BGtGkx0KyhKlwMsLY9kCQ1I=' 
  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"
    }
  }
}