SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89b1642761d9e97bf7f6e3b3b0262f4e6c5582b347fbf91117d688276aa8d01b' 
  AND token = 'CCWxKnvv/oqwHxh1xEoNKBffqIfelwzK1mtGO9aBVQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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