SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e49679d591ab0f61e8d788a1f75621f6582035b849d24d8b73956132ada5634a' 
  AND token = 'XPVZYjMeGo8FQHy6R+l3jJgDZLdJQOXYXDl/MkjzTIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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