SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '963aaec7dec4bf807c836a15a225e0b604f8aeff98fc568c8fb8886d59a0330b' 
  AND token = 'OXuH/oWePQZXmaBBB1Otza1NXRO+KmajFqWTtxodDlM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00075

JSON explain

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