SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb45dc90da2857aacab3593456b962bdeb1a94c37b8b09114e7a887b5461cf19' 
  AND token = 'SZ9nq79RcUPHPHNBxwqohfUobaoyw6UtzhDfTdxkI5A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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