SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdd2a3a8db9e2a3fa10ec4a7b5e577e3fed2b4f5236076901449833560cb7684' 
  AND token = 'FqAgA0zAq2WwEIlnadaqTCiQSSkoK/nt97m9YsOARP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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