SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aba14bb859617906eb17718d18baaf46eb81e5cbb804f477557cc54826c99edc' 
  AND token = '/7tFd8n+kusHJmorJUg4jqZU4m5+PuRhoBaHWcwYy1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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