SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5ee2544b525c9f09f1a0409e6f73a9dd7be9f7f320e4ced833339674b247a1d3' 
  AND token = 'EHqhXT/51kHz4iuGIxV2joMhsdwJ8HG/GPbt6UZJfEc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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