SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bf0b911c1ce784233e0be2101c05e4e060cd3a956f7553412f0d532f5a9b0da' 
  AND token = 'JTSNvjhSQMTQChRAn5nRIOL9Iyjb83hV34mF7KpsICE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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