SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e309e3b51ef5e8ccedcf155ebcd075b0f0a25680fd38abb46949d6afac631cf9' 
  AND token = '2qIhjubnyLMo00/qA3dusJnpXU+OsK6GESBfNGrKZ6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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