SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2bfebb571865aead97aed464cacb13446aa700c5d7e81889ca3cbbf45e68bbe3' 
  AND token = 'vPnFdoaHEbvbwYy2x8ezuu6mBGuLowrnS9SzQUt/h9Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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