SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd0e07a5cc1e981c18f0ead9a0c1e8ccb78fed2c00c08293b8170c548b8963943' 
  AND token = 'EjQodWyw5Xlbj/SHRHY3PGKDurBEPVDzRECJiZI84Gk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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