SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c24757b059d7abf4eb9c2eefcdde92f4390f92c3f1e3784c29b117e2d2c23fa2' 
  AND token = 'd3ElCRokqJYrXNxfjow531vczjxLnYt3P+fmxyPFDMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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