SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '220327e044701497e95010afe2caf6c7b3713d24fddfd4c636996ea707f03548' 
  AND token = '0LVBd0yBQ1GZ3yGqWYYzRIKQIlanZ+0ZxFPshoUY/nk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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