SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb7ad9f95b2e8bc56499c9ed9d53116abd718a1b8b3a3c1769403b0753425fe7' 
  AND token = 'jIGdIQJNaIrnLCybCpNvDhAOuDoiz7XNrVzLVCk1fJk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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