SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c5dfa837ed3dd587cbf7d0dba9410c1ff7843b0e41bb6e4023e76417acbfe1f' 
  AND token = '5A45WgCkxDuLHVCX+kwBPFfaTNYeGXsJ6g2385unz9E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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