SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae96019e4c9e83221527d0998021164ea963341cdc4bc2dd176c85d65a634f9e' 
  AND token = '7Jr0W/k+ltYtn3wrLtz160UCmZSNx/iwEu83aTnXHgQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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