SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f7377bc4412fd921f1cadea844232c578643f81977b1bbaac75047e83875db1' 
  AND token = 'jg84nNXBMNqzujfxfPPAc9h0xqNK+lJipfE2uCiGqOM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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