SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de3f3a48ad17d04d6c1167b5241f7dce65461106a0302b9ff1041d4eee5956fd' 
  AND token = 'eUyPTZJDYrEpOQ/qj0ChiIMeA21kCqZUOVSpHDVmNX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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