SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95d83c7ab1b489070e4f64c051d7157ff46e9265a44ae88b376c91dbc45c0fbb' 
  AND token = 'R5FUtWY6tuqcgiCoyXBPIqQzKs3WEI1GwRsZst2dKyc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}