SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b32ce1a33298338a3494de3248134eeab34a69cbc26f28c8a91874d238b9ecf' 
  AND token = 'si7jHlzgYlWWrFvPmQcGhKiTqS2fokxWC1Cc8MKxfn0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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