SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '738854f64b41a7de2439c1343269c34c8529d5bfd6bfeaec759ef15a7d72af57' 
  AND token = 'hx9voWRXRNzTAeCGJ3BkVn0pPOmwPMTUmHu4TkDhGv8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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