SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dbb70650b90d7d74442204eb64d6fe7c721aa2b7393f05fe9e1d5a8bdc423d81' 
  AND token = 'CKtc778CLs0+2GqF9B2szRR82SQurk9zKT9exgKALcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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