SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efb0e102dae473c3f5fa89cea564e3f82db64230b511ab515f14f3c19574e692' 
  AND token = 'hI6oK7AscL3XijQsB9M60f/jcUT+HyJs21k4SDGIw+0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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