SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ccbbbac2ddb231fb3abe524d6f05b27fc3fb1deb780e3d1824e378ff8701d1d' 
  AND token = 'HbIwxY13alCeWlThkV/WwidmhhI3Cv+y1tSKfAnqxUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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