SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfbeff08fc6091cbb3f77f5dc70237c960dafa801af25696b30cbd0a1c4aca8d' 
  AND token = 'l5y18bUwDBRRgLolXL2ytoaKlfMIvMT9aVJG+N55Xt8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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