SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '8ced491662816f8df24706722e21a3764eced0a722be5c2d72abafc0b5762f9c' 
  AND token = '6rO5GFlblzR1n6Q4/17yPfpT4OgE8zauTTvRVQCBdjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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