SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '098567d3add1397cecf6c922ace013f5020b2222a26ffb7345bccfa15ddb8e91' 
  AND token = 'XBWTmmcrSntPu85N28IMu7RyFNcpjgadbjnwPcpqfUY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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