SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63ee0c29cdcc5899b25eaca78cd125df683976b7fdaf3e3433990490ade9b6e4' 
  AND token = 'SLlBJSnFQJ8SyKLnMrCcetvLQv46yy6zaJwf6KabvBY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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