SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f76e7d6346999e30c2943848a4cfbb9e7407bce0faf42289566102954306e7b0' 
  AND token = 'HZsDifXHz1DLP7DZT5oS3JyvtWh4Bs3pPahNkrvXW04=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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