SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be5134117fa67690c84d03dd74f8028df64fe3aec30dce5f9d67d667b9cbbf11' 
  AND token = 'sZuafMrQw8aa4nJCD3qpGoPy+CDq7AjZIp1XNkEQVCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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