SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e74add45dcb32325d3a831ffe6a0ebe2fab04027c61a1ae8c4bf9723859fbb8d' 
  AND token = 'QdhO7mxULkNWtDJQuHSSnry/BEGs/8cxdOeBKUGu9+w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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