SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4dd08510bca8758eb372db83e26b7a4a3784a861000953d12c6ee98fa3211f05' 
  AND token = 'bwtT1lDfghfSIjXHCEiszMcx/So7/+Vw6GdyhIKyPCQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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