SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ee8e26526ddee92aeae967757db7e48b3af26c37c906b897ea47bd66d1332ef7' 
  AND token = 'GiOY04OFcF/rq9ByHKXFOeiOsB1cSEfBW+HqscSWj1A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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