SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bdd2d9673e0cd5874f33568f06999d4610e7cc1ba6a9dfc2d6034f951980768' 
  AND token = 'JNKVGdxYjHc+dzbDKBdsWtjBnY9FNCktNPmggOFCLdA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00101

JSON explain

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