SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9045b0b2a154537722700b39c645e9948ae57f596f5393e1457af7e1774b41f7' 
  AND token = 'ocfXw9sHpmKieFi7FTWlcuek2pEJKfMm5ZbVT/G3PgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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