SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49b6bc65da9284a1e2f40aa7d446a8db82dbed35e643b7e8a229346a11e8221e' 
  AND token = 'Gr7bMmrTXx9fspdAZC0gCmljyu+wVMMu05LEMt1Ny1w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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