SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '12f38a984436b17c908324c0ec94f33cb47c1553d1733e9269758f86a0091e8e' 
  AND token = 'XEkgjuJQtWlPY0DL8zGX5ZDCBxg2rAugOBsKBiwDZhE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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