SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd02224e9e422375a93d0e36e4049776a9f9ec7f8a336e41b17fb90c319f87f20' 
  AND token = 'FEqjit0bkXv1tG/K1Zq6dwMgsz/hBgDCXNQGbtYpNxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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