SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '557828d944b5fdadb36e4eb3b63ac22c191f6569ec0e8cc074aa76e1b98c9f67' 
  AND token = 'RZHbrMfH3Wlk9vSZ0qDZYWcfN9HoXOJyvSrDDgYhSv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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