SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10bc4fb7f49116526bf5cf82519c1d4ab5233d45fd87491c08ea26e0f9cd1ff6' 
  AND token = '+VjUV4lbK3oB/Dzm4ML9+br7bJtJHY028wSPnBp/7G0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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