SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'faf73ef37d86f2e3b0a0cf177c0ba9732a040be805f21948b18cd7289431660c' 
  AND token = 'VRh+aLryO5zSPMgPYJvK1TjoytLGEfJJ3iPLDBd5Ci8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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