SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ccb20de127ad70b9d079208d3ab1dea881bfee6299fe8b09a2565c1a4279cc5' 
  AND token = 'cHkV2MA0szuZdd30wHGVWtnrQ9zvQJxgFMirAXUN83k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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