SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc2ef9a5408f512f8abb13626d381f711edf2f5b8428e31a244347b3f111a622' 
  AND token = '3Y1mRzYDIc9O70YiFZ7AX66cIKfLx3scUaAOW3VX8bk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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