SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '92d4dea88698f0d281760cad4b0cf6a2c4ca53f4f24e68e25aa513364890426f' 
  AND token = '+YPMScZtszeGBRnn3geq1SCC3+XMTAWIjjJ5mIrd9NY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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