SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ac4d37b30a5754941e6c13ee8a0ef29f348851f98db1302ea7c6ac09c726ae7' 
  AND token = 'ATVz47qb8N4TPtfVxKEHUrTeJwJ7tMclVxyfk+yiW/Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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