SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '520dfabbf78a562c25bd88d57734cfeec60f82f002b86571072c47728e184d0e' 
  AND token = 'ecQ+L2b9ZC1LBHqBnGrzrIw+jWx7XfKn10MZvf+CjYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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