SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13607eb58b45a8e17743ff84535559eadbf5e7301ec5eec3d3322a55b05214f8' 
  AND token = 'GcLGM9tu0gL8Kiiws1JAmohOSExSqGNzT/V/llVF80s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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